Loretto College School (a.k.a. Loretto College, or Loretto), formerly the Loretto Abbey Day School and Loretto Abbey Day School and College, is a Catholic high school for girls in Toronto, Ontario, Canada. It is operated by the Toronto Catholic District School Board, formerly the Metropolitan Separate School Board. The institution was founded by the Loretto Sisters (Institute of the Blessed Virgin Mary) in 1915, whose founder (Blessed Mary Ward) advocated for excellent education for young women so that they might "do great things". The name "college" refers to the school's association with Loretto College, a component of the University of St. Michael's College, part of the University of Toronto.